What do you want to do, disable the use of Ctrl-Alt-Del? If so, this should do the trick:
VB Code:
Private Declare Function SystemParametersInfo Lib "user32" Alias _
"SystemParametersInfoA" (ByVal uAction As Long, ByVal uParam As Long, _
ByVal lpvParam As Any, ByVal fuWinIni As Long) As Long
Private Sub DisableCtrlAltDelete(bDisabled As Boolean)
Dim x As Long
x = SystemParametersInfo(97, bDisabled, CStr(1), 0)
End Sub
Private Sub Command1_Click()
DisableCtrlAltDelete (False)
End Sub
Private Sub Command2_Click()
DisableCtrlAltDelete (True)
End Sub
On the other hand, if this isn't what you want to do then give some more specifics and I'm sure we can work something out.